System for the selection of electric circuits.



No. 795,820. r PATENTED AUG. 1, 1905. A. G. COX.

SYSTEM FCR'THE SELECTION OF ELECTRIC CIRCUITS.

' APPLICATION FILED JAN. 27. 1902.

3 SHEETS-SHEET 1.

WI LWEEEEE Im/E'WzUY" No. 795,820. PATENTED AUG. 1, 1905.

A. G. 00X. v I SYSTEM FOR THE SELECTION OF ELECTRIC menus.

AIEPLIOATION FILED JAIi. 27. 1902.

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,A, G. COX.

SYSTEM FOR THE SELECTION OF ELECTRIC CIRCUITS;

APPLIOATION FILED JAN. 27, 1902.

3 SHEETS-SHEET 3,

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UNITED STATES PATENT OFFICE.

ANSON Gr. COX, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO SPENCER N.RICHARDSON AND RICHARD P. ELLIOTT, TRUSTEES.

Specification of Letters Patent.

Patented Aug. 1, 1905.

Application filed January 27, 1902. Serial No. 91,420.

To all whom it may concern.-

Be it known that I, Anson G. Cox, of Boston, county of Suffolk, andState of Massachusetts, have invented a new and useful improvement inSystems for the Selection of Electric Circuits, of which the followingis a specification.

My invention relates to a selective system whereby an operator canselect and close one or a number of local circuits at distant stations;to select one of a number of telephones; to start or stop one of anumber of motors; to light any one of anumber of lights or combinationsof lights; the operation of type-writers, printing-telegraphinstruments, type-setting machines, or any other instruments or machineswhere it is desired to operate difierent parts or combinations of partsof same independently of the remaining portions by the use of anelectric current.

My invention consists in the employment in main-line circuits,so-called, of a system of relays either in single sets or groups ofsets, together with means for changing the direction of the flow ofcurrent and strength in said main-line circuit.

It also consists of the employment of resistance-coils and means forcutting them in or out of the main-line circuit at will. In theemployment of resistance-coilsin connection with the means used forthrowing them in or out of circuit lam able to maintain a constantdifference of strength between the strong and the weak currents. hereinshown and described I employ but two current strengths, three or morestrengths of current may be used without materially changing theinstruments, with the result that a greater number of local circuits maybe selected and closed.)

1 provide a series of contacts operated by any suitable means to connectthe batteries with the main-line circuits and for throwing theresistance-coils in or out of the circuits. A portion of these contactsare what is known as pole-changing contactsd. 0., they enable me topresent either terminal of the batteries to the ends of the main-linecircuits at will,.causing the current to flow through the relays ineither direction, as desired. The means employed by me in my selectivesystem consists of main-line circuits, a source of electrical energy,polarized and non-polarized relays, contacts, some of which are what is(While in the system,

known as pole changing contacts, and when it is desired to increase thenumber of selections resistance-coils adapted to be cut in or out of themain-line circuits. 'When two or more groups of relays are used, 1cmploy a main-line circuit for each group and a non-polarized relayhaving its magnets in circuit with each of the main-line circuits. Bythese means I can send impulses over one or more of the main-linecircuits of varying strengths and in diflerent directions.

One object of my invention is to enable the operator to select one ormore of a number of local circuits by the employment of a minimum numberof current strengths and mainline wires.

Another object is to provide a simple selective system easily operatedand maintained and one where but one impulse over each main-line circuitwill select and close the desired local circuit. Where two main-linecircuits are used, one impulse over each, both sent theoretically at thesame instant, will select and close the desired local circuit?l. a, mysystem is not what is called a progressive o'r step-by-step system.

My new system is shown as applied to the selection of a series of localcircuits having in circuit therein magnets the armatures of which areattached to and operate a number of slides or combs.

In the drawings which accompany and illustrate my invention, Figure l isa side elevation of my new form of polarized relay. Fig. 2 represents aplan of the same. Fig. 3 is a side elevation of the switch-magnet usedby me. Fig. 4 represents a plan of the same. Fig. 5 is a plan of my newnon-polarized relay. Fig. 6 is a side elevation of the same. Fig. 7 is adiagrammatic view of my improved selective system, showing the mainlinecircuits,batteries, relays, switch-magnets, and contacts in position toselect and energize a group of three local magnets. Fig. 8 is adiagrammatic view of my improved selective system and the relays andswitchmagnets, together with the local battery, circuits and magnetstherein, which perform the work required.

1n the drawings accompanying this specification, in which Ihaveillustrated the principle of my invention and the mode in which Ihave applied it, the main-line circuits are short-circuited at lines 25and 45 and the batteries Y and Z cut out, together'with theresistance-coils I) and D and all the linewiring between the wires 20and 44 and the contact-terminals (6 a a a, a a a", and a when the systemis at rest or a message is being received from the distant station. Thecontacts a c serve to cut the batteries, resistance-coils, andcontact-terminals, and all wiring between said terminals and the wirse20 and 44 into the main-line circuit when it is desired to send amessage. The means for short-circuiting the main line or cutting thecontact-terminals and main batteries into the main-line circuits arelocal and are operated by a local battery.

60 and represent contacts, one of which is operated with eachcombination used. When the contact a, is pressed against the terminalsof the wires 1 and 2, the current flows from the battery X through line3 to line 1, through contact-piece a to line 2, thence to switch-magnetM to line 4, line3, to the said battery X, thus preparing to throw thecontact-circuits 11, 12, 13, 14, 104, 105, 106, 107, 87, 88, 89, 90,108, 109, 110, and 111 into the main-line circuit. When the currentflows through the switch-magnet M, its armature 6 is drawn away fromcontacts 5 and 6 and its contacts 7 and 8 into contact with theterminals of wires 21 and 45 and flexes the spring S, which normallyholds it against the contacts 5 and 6. The keys c and a are made tocontact with the terminals of the wires opposite them at the same timethe contact a is made to contact with. the terminals of the wires 1 and2 in the particular case illustrated. By pressing the double contact (0against the terminals of lines 11 12 13 14 the current flows from thebattery Y through lines 15 16 12, contact in a, lines 11 17 18 19 20 21,to contact 7, thence to line 22, and through switch-mag net M lines 24and 25, through the magnets M in the non-polarized relay R line 25,switch-magnet M line 25 to polarized relay R, to line 25, the ground,lines 26 27 28 29 to line 14, contact (4 line 13 to lines 34 and 35, andthence to the battery Y. By causing a current to energize theswitch-magnet M its armature is drawn against its poles and its contact36 against the terminal of wire 47, thereby cutting in the main-linecircuit L When the double contact a is pressed against the terminals ofthe wires 37, 38, 39, and 40, a current flows from battery Z throughlines 41 42 38, contact in a to lines 37 43 44 45, contact 8, line 46,contact 36 to lines 47 48 49, through magnetM of the non-polarized relayR to switch magnet M, line L, through polarized relay R to line 49, theground, lines 26 27 28 29 40, to the contact on a to lines 39.54 55,back to the other terminal of battery Z.

In tracing out the contact-circuits we have described the operation ofthe switch-magnets M and M by a strong currenti. a, without theintroduction of the resistancecoils D and D into the main-line circuits.These switch-magnets M and M have springs S and SF attached to theirarmatures, each of suflicient strength to resist the magnetic attractionof themagnets when the resistancecoils D and D are out into circuit, theflow of current impeded, and the so-called weak current is passing overthe lines; but when the resistance-coils D and D are cut out the magnetshave a pulling strength sutficient to overcome the resistance of thesprings S and 8* and cause the armatures 6* and b to be drawn towardthem and the insulated contacts and 31 to press against the terminals ofwires 59 and 67, as shown in Fig. 8 of the drawings.

The operation of the relay R is as follows: In the operation of myselective system one of the main line circuits is always closed ahead ofthe other. As the current in line L passes through magnet M in relay Rand the current in line L passes through magnet M in said relay R itfollows that both magnets M and M in said relay R are energized at eachoperation of the system in this particular adaptation of it. Thearmature I) of relay'R is what is known as a floating armaturez'. 0, itis free to swing either to the right or left and is drawn to contactwith the poles of whichever of magnets 1W1 or M is first energized andis held there during the time the current is flowing in the main-linecircuits L and L. I The relay R is so constructed that when the armatureis in contact with the poles of magnet M the space between said armature6 and the poles of the magnet M is so great that though theresistance-coil D is cut into line L and the current flowing therein isweak and the resistance-coil D is cut out of line L* and the currentflowing therein is strong yet the magnetic attraction of said magnet Mwill not be suflicient to draw said armature b away from the poles ofmagnet M and its contact-point away from the terminal of line 63. Whenline L is closed through its battery Z first and the current flowstherein before acurrent is passed through line L the armature b is drawnto contact with the poles of the magnet M in relay R and held in contacttherewith, although a strong current is passed through line L and themagnets 1 7 of said'relay R The polarized relays R and R are identicalin construction, and a description of one will suflice for the other.These relays form the subject-matter of my application, Serial No.117,979, filed August 1, 1902, in which a detailed description will befound. For a better understanding of the invention covered in thisapplication, however, the following description is inserted: In thepolarized relay R, 0 represents a permanent magnet, which tact a.

may be mounted on any suitable insulating material. is the back strap,to which the cores 0 0 of the magnet-coils M and M are attached. 0 0represent pole-piecessecured to the outer end of the cores 0 0 whichpolepieces are separated to receive the armature between them. 0* isaframe secured to the cores 0 0 of the magnets M and M by screws 0 0passing through the pole-pieces 0 0 The frame 0* is provided with abearing 0, in which the armature is pivoted in manner to swing freelysidewise. The arma ture has a pin 0 inserted near its outer end,

against which the outer ends of the flat springs 0 0 bear, their innerends being secured in the post 0 The pin 0 projects through the aperture0 in the plate 0* and has free play therein. A pin 0 is inserted in theframe 0 to provide a stop to limit the inward movement of the springs 00 The tension of the springs 0 0 is controlled by the adjustingscrews 00. It will be understood that according as a positive or negativecurrent flows through the relay R the armature is attracted against theresistance of one of the springs 0 and its contact pressed against theterminal of the wires 57 or 95, as the case may be. The contact on thearmature b is attached to local wire 56, as shown in Fig. 8.

When the armature b is in position equidistant between thepole-pieces 00 the springs 0 0 bear against each side of the pin 0 with the pin 0between them, and therefore always retain said armature in a centralposition except when a current is flowing through the magnet-coils M andM Either of the relays M or M may be used to cut the contact-circuitsinto the main-line circuits. When it is desired to energize mainlinecircuit L first, the relay M is used and is energized by the battery Xthrough con- If it is desired to energize the main line L first, relay 15 is energized by the battery X through the contact a. The battery X isused to operate the relays M and M and is local. The relays M and M arein branches of the main-line circuits L and L their magnets 'beingenergized by the current flowing therein, although one only of thesemagnets is energized at a time. By operating the magnet M first throughits contact a the armature b of the magnet M is drawn toward its polesand away from the contacts 5 and 6 and its contacts 7 and 8 pressedagainst the terminals of the lines and 21, thereby causing a current toflow through main-line circuit L by means of the contact-plate a firstcutting in relay M thereby cutting out relay M When in order to selectthe desired local circuit it is necessary to energize main-line circuitL first by means ofits battery Z, the contact a is pressed against theterminals of wires 73 and 74, when the current from battery X will flowthrough line 3 to line 73, contact a, line 74 to relay M thence by lines4 and 3 to batteryX. This will energize the magnets of relay Mattracting its armature against the resistance of spring S causing thecontacts 76 and 77 to contact with the terminals of Wires 21 and 45, (itbeing understood that the spring S has drawn the armature 7) of magnet Maway from the terminals of lines 21 and 45 and its contacts 5 and 6against the terminals of lines 32 and 33, thus leaving that end of wires21 and 45 in space.) Having brought the contacts 76 and 77 against theterminals 21 and 45 by pressing the key 0* against terminals of wires 73and 74, I press the contact 0 against the terminals of wires 78, 79, 80,and 81, and a current will flow from battery Z, to line 41, to line 42,thence to line 80, through contact a, to lines 81 and 29, line 28, lines27 and 26 and ground, to line L, relay R switch-magnet M, magnets M ofrelay R line L, to line 48, line 83, thence through the coils of relay Mline 83, contact 77, line 45, thence through line 44, resistance-coil D,line 84, line 78, to contact a, lines 79 54 55, and to the other pole ofthe battery Z, thus energizing the magnet M", causing it to attract itsarmature 6 against the tension of the spring S, causing its contact 85to press against the terminal of line 86, thereby closing the main-linecircuit L at' that point; but the current in flowing through line Lenergized the magnet M of relay R first, thereby holding the armature 7fagainst the poles of magnet M in opposition to magnet M in theillustration now being given I use the contact a by pressing it againstthe terminals of wires 87, 88, 89, and 90. The current will thereby flowfrom the battery Y, through lines 15,16, and 88, contact (6 to 87 91,through resistance D, lines 18, 19. 20, and 21, contact 76, line 92, tocontact 85, lines 86 24 L magnet M of relay R through the coils ofswitch-magnet M to the coils of relay R, line 25 to ground, lines 26,27, 28, 29, and 90, through the other half of contact a, to lines 89 3435 to the negative pole of battery Y. In the operation of sending thecurrent through the two main-line circuits L and If just described aresistance-coil D was inserted or short-circuited into main-line circuitL and the resistance-coil D was short-circuited into main -line circuitL thereby causing a weak current, so called, to flow through bothcircuits. Furthermore, by the use of the contact-key a a positive effectwas produced in main-line circuit L and a negative effect in main-linecircuit L by the use of the contact a Having shown that what I will terma plus and minus and a weak and a strong current can be sent through themain-line circuits L and L and that the armatures and b of the polarizedrelays R and R are drawn to the right by a plus current and to the leftby a minus current and that the ,armatures b" and b of the switchmagnets M and M are drawn to their respective poles by a strong currentonly, I will now describe the selection of the local circuits. In theparticular case illustrated I have shown the local circuits operatingmagnets N N and N, they being selected and closed through the localbattery W.

Referring to Fig. 8, it is seen that the terminals of local battery Ware attached to the armatures and b of the relays R and R by lines 56and 71. A strong plus current was caused to flow through main-linecircuit L first, which produces a plus effect in relay R, draws thearmature 6* ot' the switch-magnet M to its pole against the resistanceof'the spring S and swings the armature F of the relay R against thepoles of the magnet M The effect of the movement of the armatures 5 b,and 6 just described, is to press the contact on armature against theterminal of wire 57. The insulated contact 30, to which the wire 57 isattached, is pressed against the terminal of wire 59 and the contact onarmature 6 against the terminal of wire 63. While the above-describedoperation was taking place main-line circuit L was closed through thecontact a and the relay Miand a strong plus current caused to flowtherein, which produced a plus efliect in relay R causing the contact onarmature b to press against the terminal of wire 69 and the armature ofswitch-magnet M to be drawn to its poles against the resistance of thespring S, thereby pressing the insulated contact 31, to which wire 69 isattached, against the terminal of wire 67. The effect of the operationof relays R R and switch-magnets M and M*, as just described,is asfollows: The current from battery is caused to flow through wire 56 toarmature 6 line 57, to contact 30, thence through line 59, throughmagnet 1 lines 60 61 63, through magnet N, line 63, armature 6", lines64: 65 66, through magnet N line 67, to insulated contact 31, to line69, armature b and wire 71, to the other terminal of battery WV, thusenergizing magnets N N, and N causing them to perform the work required.By pressing the contacts a (0, and ((7 against terminals of wires 73 and74, wires 78, 79, 80, and 81, and wires 87, 88, 89 and 90 a plus effectwas produced in relay R, its armature If swung to the right, and thecontact thereon pressed against the terminal of wire 57, a minus efi'ectproduced in relay R its armature 6 moved to the left, and its contactpressed against the terminal of wire 96. At

. the same time the spring S of the switchmagnet M has held the contacts30 and 93 of the armature against the terminals of wires 99 and 100 andthe spring 5* of the switchmagnet M has held the contacts 31 and 101 ofthe armature 5 against the terminals of wires 97 and 98, thereby causingthe current from battery WV to flow through wire 56 to the contact onarmature b thence through wire 57, insulated contact 30, wire 100,through the coils of magnetN, wires 102 61 63, magnet N, armature 6wires 64 65 103, magnet N*,'wire 97, contact 101, wire 96, armature band wire 71, to the battery IV, thereby energizing magnets N N and N*,causing them to perform the work required. In one case illustrated thecurrent was caused to flow through main-line circuit L first, therebyenergizing magnet M to close the circuit through main-line circuit If".In the latter case main-line circuit L was energized first and thecurrent caused to flow through and energize the magnet M to close thecircuit through main-line circuit L It will be understood that the wiresIf and L after they leave the relays R R as shown at the top of Fig. 7,are supposed to connect with one or more distant stations, and the wire26 is grounded to also form a connection with the distant station. Saiddistant station is of course provided with an equipment similar to thatshown in Figs. 7 and 8. When it is desired to operate the instrument ofthe station shown from a distant station, the armatures Z) and b" are innormal position with their contacts 5 6 and 7 8 in contact with theterminals of the wires 32 33 and 3233, the terminals of which are thecontacts 5 and 6, which contacts are insulated from each other, and thecontacts 7 and 8 are in communication with the common return 26, asshown in Fig. 7. Hence impulses sent from a distant station over theline-wire 25 will pass through the instrument R M M wires 24 33, contact5, wire 33, contact 7 and back through common return 26. On the otherhand, when impulses are sent over the wire 4C9 they will pass throughinstrument R M M, wires 49 18 32, contact 6, contact 6, line 32, contact8*, and back through common return 26 to the ground connection.

I do not limit my invention to-any fixed number of main-line circuits,groups of relays, and switch-magnets and strengths of current. Each maybe varied at will. The number of each depends solely on the number oflocal circuits to be selected and closed. The greater the number ofmain-line circuits, groups of relays and switches, and strengths ofcurrent there are used in a system the greater the number of localcircuits which may be selected and closed.

Having described my improved selective system, what I claim is g 1. Inaselective system, a plurality of mainline circuits; a source ofelectrical energy for each; means for causing currents of difierentpolarities and strengths to flow in said mainline circuits; means incircuit in each of said main-line circuits so constructed and arrangedthat by their cooperation one or more local circuits may be selected bythe joint action of single characteristic impulses one over each of twoof said main-line circuits.

2. A selective system having for its purpose the selectlon and closingof any one or more of a plurality of local circuits located at a distantpoint, by means of the combined action of single characteristic impulsesone over each of a plurality of main-line circuits, the selective meansconsisting of a plurality of mainline circuits, a polarized relay and aswitchmagnet in each of said mainline circuits; means for sendingcharacteristic impulses over said main-line circuits; and means wherebysingle characteristic impulses one over each of two of said main linecircuits will cause the instruments therein to cooperate to select oneor more local circuits.

3. A selective system comprising means for the selection and closing ofone of a plurality of local circuits at a distant point by a singlecharacteristic impulse over each of two mainline circuits,said meanscomprising two mainline circuits, a source of electrical energy foreach; a polarized relay and a switch-magnet in each main-line circuit;means for varying the strength of current sent to line in each main-linecircuit; means for changing the direction of flow of current in eachmain-line circuit; said relays and switch-magnets being so constructedand arranged that the combined action of a single characteristic impulseover each main-line circuit will cause said relays and switch-magnets tocooperate to select and close any one of a plurality of local circuits.

4. In a selective system having a plurality of main-line circuits, meansin circuit in each of said main-line circuits, so constructed andarranged that the combined action of a single characteristic impulsesent over each of two main-line circuits will cause theinstrumentalities therein to combine for the selection of a localcircuit located at a distant point.

5. A selective system comprising two mainline circuits; a source ofelectrical energy for each; a polarized relay and a switch-relay in eachmain-line circuit; a relay having two sets of magnets, one in eachmain-line circuit;

means for energizing one main-line circuit before the other; means forvarying the strength of current in each of said main-line circuits; andmeans for causing the currentto flow in either direction in each of saidmain-line circuits; and means whereby asingle characteristic impulseover each main-line circuit will cause the selection and closing of anyone or more of a plurality of local circuits.

6; A selective system comprising two mainline circuits; a source ofelectrical energy for each; a polarized relay and a switch-relay in eachmain-line circuit; a relay having two sets of magnets, one in each main-line circuit; means for energizing one main-line circuit before theother; means for varying the strength of current in each of saidmain-line circuits; and means for causing the current to flow in eitherdirection in each of said main-line cir cuits; and means whereby asingle characteristic impulse over each main-line circuit, one sent toline before the other, will cause the selection and closing of any oneor more of a ANSON G. COX.

Witnesses:

RICHARD P. ELLIOTT, WM. (3. RICHARDSON.

